﻿// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information
// 
// Licensed to the Apache Software Foundation (ASF) under one or more
// contributor license agreements. See the NOTICE file distributed with
// this work for additional information regarding copyright ownership.
// The ASF licenses this file to you under the Apache License, Version 2.0
// (the "License"); you may not use this file except in compliance with
// the License. You may obtain a copy of the License at
// 
// http://www.apache.org/licenses/LICENSE-2.0
// 
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// 

using System;
using System.Text;
using System.IO;

using log4net.Core;
using log4net.Util;
using log4net.DateFormatter;

namespace log4net.Util.PatternStringConverters
{
    /// <summary>Write the UTC date time to the output</summary>
    /// <remarks>
    /// <para>
    /// Date pattern converter, uses a <see cref="IDateFormatter"/> to format 
    /// the current date and time in Universal time.
    /// </para>
    /// <para>
    /// See the <see cref="DatePatternConverter"/> for details on the date pattern syntax.
    /// </para>
    /// </remarks>
    /// <seealso cref="DatePatternConverter"/>
    /// <author>Nicko Cadell</author>
    internal class UtcDatePatternConverter : DatePatternConverter
    {
        /// <summary>Write the current date and time to the output</summary>
        /// <param name="writer"><see cref="TextWriter" /> that will receive the formatted result.</param>
        /// <param name="state">null, state is not set</param>
        /// <remarks>
        /// <para>
        /// Pass the current date and time to the <see cref="IDateFormatter"/>
        /// for it to render it to the writer.
        /// </para>
        /// <para>
        /// The date is in Universal time when it is rendered.
        /// </para>
        /// </remarks>
        /// <seealso cref="DatePatternConverter"/>
        protected override void Convert(TextWriter writer, object state)
        {
            try 
            {
                this.m_dateFormatter.FormatDate(DateTime.UtcNow, writer);
            }
            catch (Exception ex) 
            {
                LogLog.Error(declaringType, "Error occurred while converting date.", ex);
            }
        }

        /// <summary>The fully qualified type of the UtcDatePatternConverter class.</summary>
        /// <remarks>
        /// Used by the internal logger to record the Type of the
        /// log message.
        /// </remarks>
        private static readonly Type declaringType = typeof(UtcDatePatternConverter);
    }
}
